Tailgate for a rear loader refuse vehicle

ABSTRACT

A tailgate for a rear loader refuse truck. The tailgate has parallel vertical side walls and a hopper bottom. The hopper bottom has a generally V-shaped longitudinal section. There are a pair of parallel, straight, downwardly and rearwardly inclined guide tracks, one in the upper forward part of each side wall. A generally L-shaped packer blade is pivoted at the upper end of the upright bar of the L on a cross rod carried by slides which are movable along the guide tracks by power means. A pair of extensible cylinders are pivotally connected at the upper rear corners of the side walls and to the packer blade at points near the angle of the L. The packer blade is cycled by retracting the rear cylinders, moving the slide down the guides, extending the rear cylinders and then moving the slides up the guides, to pass backwardly over refuse in the hopper, to come down behind the refuse and to sweep it forwardly along the hopper bottom and upwardly into the truck body.

United States Patent 1 Herpich et al.

[ 1 July 17, 1973 TAILGATE FOR A REAR LOADER REFUSE VEHICLE [75]Inventors: William A. l-lerpich; Donal W. Chaney, both of Galion, Ohio;George W. Palmer, Durant, Okla.

[73] Assignee: Peabody Galion Corporation,

Galion, Ohio 22 Filed: July 23, 1971 21 Appl. No.: 165,517

Herpich et al.

Primary Examiner-Albert J. Makay Attorney-Owen & Owen [57] ABSTRACT Atailgate for a rear loader refuse truck. The tailgate has parallelvertical side walls and a hopper bottom. The hopper bottom has agenerally V-shaped longitudinal section. There are a pair of parallel,straight, downwardly and rearwardly inclined guide tracks, one in theupper forward part of each side wall. A generally L- shaped packer bladeis pivoted at the upper end of the upright bar of the L on a cross rodcarried by slides which are movable along the guide tracks by powermeans. A pair of extensible cylinders are pivotally con nected at theupper rear corners of the side walls and to the packer blade at pointsnear the angle of the L. The packer blade is cycled by retracting therear cylinders, moving the slide down the guides, extending the rearcylinders and then moving the slides up the guides, to pass backwardlyover refuse in the hopper, to come down behind the refuse and to sweepit forwardly along the hopper bottom and upwardly into the truck body.

4 Claims, 8 Drawing Figures Patented July 17, 1973 3 Shoots-Shut lINVENTORS 2 A .Hz

I I ILLIAM RPIEH, CRANE 52 WP MEH.

.UUNAL l l BEE:

Patented July 17, 1973 3,746,192

3 Shuts-Shut 2 INVENTORS: WiLLIAM A. HEEPICH, .UUNAL W EHANEY,

GEUREE IMP Jx IEH. .EY' M lTTys.

Patented July 17, 1973 3,746,192

3 Shuts-Shut 5 INVENTORS:

- WJ'LLIAM A. HEHPILH,

5'7 17mm; I/IZ EHANEY;

[3.205255 I I/TPALMER.

Fi-E- By gun AT T 75.

TAILGATE FOR A REAR LOADER REFUSE VEHICLE BACKGROUND OF THE INVENTION Atailgate according to the invention is designed for use on a refusevehicle which has an open rear end. The tailgate comprises mechanism forpacking refuse into the vehicle body. Workers empty refuse cans througha rear loading opening into a hopper in the bottom of the tailgate. Whena sufficient number of refuse containers have been emptied into thehopper, hydraulic mechanisms are actuated to sweep a packer bladethrough the hopper to move the refuse forwardly and into the open bodyof the refuse vehicle. After the body has been filled, the truck isdriven to a disposal center. The tailgate is swung open and the refuseemptied from the body, either by tilting the body for dumping or by anejector plate.

Several primary criteria are important in the design of such a tailgate.These are:

1. That the bottom side of the loading opening at the rear of thetailgate be at a relatively low level compared to the street level tominimize the distance which operators have to lift refuse cans.

2. That the refuse hopper have as large a capacity as possible withinthe maximum dimensions of the tailgate which are permissible so as toallow as many refuse containers as possible to be dumped into the hopperbetween cycles of the packer blade.

3. That the packer blade be actuated by means, usually hydraulic, havinggood mechanical advantage so that adequate power may be applied to thepacker blade for moving the refuse out of the hopper, for crushing orbreaking many objects usually encountered in refuse, which wouldinterfere with the packing operation.

4. That the packer blade have a cycle of operations which insures thatit passes backwardly over the refuse in the hopper at the beginning ofits cycle in order to avoid sweeping any of the refuse out of the rearloading opening of the tailgate during the cycle.

5. That the packer blade operating mechanism be responsive to jams. Forexample, if an object such as a bedspring or a massive timber wereinserted part way into the loading opening of the tailgate, the packerblade would not be able to break or cut this object and the cycle wouldjam. Under such circumstances, the packer blade operating mechanismshould respond to the jam by either elevating the packer blade torelieve the jam or by moving it forwardly away from the object which isjamming its action.

It is therefore the principal object of the instant invention to providea tailgate for a rear loader refuse vehicle in which the packer blade isactuated by hydraulic cylinder means or the like for movement through acycle wherein it travels backwardly above the level of refuse in theloading hopper, downwardly behind the refuse and forwardly to move therefuse into the open rear end of the truck itself, the movement of thepacker blade being responsive to jammed conditions in order to alleviatesuch conditions automatically.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view in elevation,partly broken away, and generally illustrating a tailgate embodying theinvention as mounted on the rear of a refuse truck;

FIG. 2 is an end view in elevation taken from the position indicated bythe line 22 of FIG. 1 and shown on an enlarged scale;

FIG. 3 is a fragmentary somewhat diagrammatic view in vertical,longitudinal section taken generally along the line 3-3 of FIG. 2'andshown on a further enlarged scale;

FIG. 4 is a view similar to FIG. 3, but shown on a smaller scale, andillustrating the position of the packer blade and its actuatingmechanism midway in the rearward leg of its operating path;

FIG. 5 is a view similar to FIG. 4 but illustrating the mechanism duringthat portion of its path commencing at the rear and moving downwardlytoward the bottom of the refuse loading hopper and en route to theforward position illustrated in FIG. 3;

FIG. 6 is a fragmentary view, partly in section and partly in elevation,taken along the line 6-6 of FIG. 3;

FIG. 7 is a fragmentary view, part in section and part in elevation,taken from the position indicated by the line 7-7 of FIG. 2; and

FIG. 8 is a fragmentary, detailed sectional view taken along the line 88of FIG. 7.

DESCRIPTION OF PREFERRED EMBODIMENT A tailgate embodying the inventionis generally indicated by the reference number 20 and is illustrated inFIG. 1 as being mounted on the rear of a body 21 of a refuse truckgenerally indicated by the reference number 22. The body 21 has an open,generally rectangular rear end defined by a perimeter frame 23, whichrear end is inclined from top to bottom in a rearward direction. Thebody has a floor 24 and an interior, hydraulically actuated ejectorplate 25. The tailgate 20 is pivotally connected to the body 21 bymassive ears 26 and pivot pins 27 so that it can be swung upwardly andrearwardly to the position fragmentarily illustrated in dotted lines inFIG. 1, and indicated by the reference number 20a, by the action of apair of elevating cylinders 28, one at each side of the body 21 andpivotally connected to the ears 26 and by massive pivot pins 29 to sidewalls 30 of the tailgate 20.

The side walls 30 are laterally spaced from each other and extendbetween a perimeter frame 31 at the front of the tailgate 20 and rearframe uprights 32 at the rear of the tailgate 20. The frame 31 and frameuprights 32 also mount a hopper bottom 33 which extends across thebottom of the tailgate 20 and a top (not shown) may also be erected toclose off the top of the tailgate 20, being secured to the side walls30, the frame 31 and the uprights 32. The entire tailgate structure isadequately braced and strengthened by suitable side wall frame memberssuch as the illustrated channels 34, 35 and 36. The side walls 30 andthe top and rear edge of the hopper bottom 33 define between them aloading opening generally indicated by the reference number 37 at therear of the tailgate 20 through which refuse containers and the like maybe emptied as shown in FIGS. 1 and 2.

A heavy packer blade, generally indicated by the reference number 38, ismounted interiorly of the tailgate 20 extending across the tailgate 20and movable through a cycle with its lower edge 39 traversing a pathillustrated in FIG. 3 as consisting of five legs between the letters,thusly: A-B, B-C, C-D, D-E, and E-A. Movement of the packer blade 38and, particularly, its lower edge 39 through the path just identified iseffected by the sequential actuation of two pairs of cylinders 40 and41. In the arrangement illustrated in the drawing, the packer blade 38has two arms, an upper arm 42 and a lower arm 43, with its lower edge 39being defined by the lower end of the lower arm 43. The arms 42 and 43are assembled in a generally L- shaped longitudinal configuration, withthe upper arm 42 extending downwardly and rearwardly and the lower arm43 extending forwardly from the apex of the L.

Pistons 44 of the power cylinders 40 are pivotally mounted to heavypivot pins 45 mounted at the upper rear corners of the side walls 30.The lower ends of the cylinders 40 are pivotally attached to stub pins46 (see FIG. 3 particularly) which are welded or otherwise rigidlymounted in a trough 47 extending transversely across the packer blade 38and forming a part of its structure. The point of attachment of the endsof the cylinders 40 to the stub pins 46 lies in the upper arm 42 of thepacker blade 38 but near the apex of the I. defined by the arms 42 and43.

The power cylinders 41 are mounted, one on each outer side of itsrespective sidewall 30, by clevises 48 located near the lower rearcorners of the side walls 30 and supported by rigid cross members, (notshown). The power cylinders 41 extend upwardly and forwardly toward theupper front corners of the side walls 30 and their rods 49 extendlongitudinally into the open lower ends of U-shaped track covers 50. Thetrack covers 50 overlie elongated track slots 51 formed in the sidewalls 30 by channels 36.

The upper end of each of the rods 49 is pivotally connected to a slideblock 52 which is adapted to reciprocate in the interior of the trackcover 50 upon extension and retraction of its rod 49. The slide blocks52 carry a cross member 53 (see FIG. 6) which is rigidly connected bygusset plates 54 to the upper comers of the packer blade arm 42. Thusextension and retraction of the power cylinders 41 and their rods 49results in sliding the blocks 52 back and forth in the track slots 51.

Retraction and extension of the cylinders 40 and their rods 44 swingsthe packer blade 38 angularly around the pivot point provided by thecross member 53.

Movement of the bottom edge 39 of the packer blade 38 from Position A(FIG. 3) to Position B (FIG. 4) along the curved leg A-B, is effected byretracting the rod 44 of the cylinder 40 to swing the packer blade 38backwardly and upwardly. The leg A-B is thus an arcuate path drawnaround the center of the cross member 53. Movement of the lower edge 39of the packer blade 38 from Position B to Position C, along the curvedleg B-C is effected by retracting the rods 49 of the cylinders 41 untilrollers 55 (see FIG. 4) mounted at each side of the packer blade 38strike a pair of guide bars 56 one of which is mounted at each side ofthe tailgate 20 on the respective side wall 30.

The guide bars 56 function to guide the movement of the lower edge 39 ofthe packer blade 38 along a straight leg C-D downwardly across theloading opening 37. This movement is effected by continued retraction ofthe piston rods 49 and simultaneous slight extension of the piston rods44 from their fully retracted positions as illustrated in FIG. 4. Inmoving from Position B to Position C, the power cylinders 41 retracttheir rods 49 until the rollers 55 strike the guide'bars 56. Thisincreases the resistance to movement and automatically switches valvingto admit power oil to the now retracted cylinders 40 to extend theirrods 44 slightly as the cylinders 41 continue to retract. The cylinders40 continue to extend their rods 44 to full extended position until thelower edge 39 of the packer blade 38 reaches Position D. Thissimultaneous action of continued retraction of the cylinders 41 andextension of the cylinders 40, results in pushing the packer blade edge39 downwardly along the leg C-D, being guided by the rollers in contactwith the guide bars 56. This movement is seen by comparing FIGS. 4 and5.

Upon reaching Position D, the cylinders 41 have fully retracted theirrods 49 and the continued feeding of power fluid to the cylinders 40results in further extending the rods 44 to move the lower edge 39 ofthe packer blade from Position D as illustrated in FIG. 5 to Position Eas illustrated in broken lines in both FIGS. 3 and 5.

The leg D-E is arcuate, representing the movement of the lower edge 39of the packer blade 38 around the center provided by the cross member53. A portion 57 of the hopper bottom 33 is cylindrical in shape andextends downwardly and forwardly from a lower lip 58 which defines thebottom of the loading opening 37. The hopper portion 57 may beconsidered to be one arm of a generally V-shaped bottom in longitudinalsection.

Further movement of the lower edge 39 of the packer blade 38 fromPosition E to Position A, along the leg EA (see FIG. 3) is effected byextending the cylinders 41 to move slide blocks 52 along the track 51from their lowermost position (FIG. 5) to their uppermost position (FIG.3) while maintaining the cylinders 40 in fully extended position. Theleg E-A is not arcuate around the center provided by the cross bar 45because, although the cylinders 40 swing around that center, the upperend of the packer blade 38 as carried by the slide blocks 52 is movingupwardly along the track 51. The shape of a forward hopper portion 59 isdefined by the leg E-A through which the lower edge 39 of the packerblade 38 is moved during this portion of its cycle.

As can best be seen by reference to FIG. 3, this forward portion 59 ofthe hopper bottom 33 constitutes a second arm of the generally V-shapedhopper bottom 33 and blends into a downwardly directed body apron 60which leads upwardly to the level of the body floor 24. Extension of thecylinders 41 to the bottom edge 39 along the leg E-A is effected by theresulting hydraulic pressures in the control system which occur when thecylinders 40 reach their fully extended position at E (dotted lines FIG.3 and FIG. 5}.

In the event that some heavy, non-frangible item is partially insertedthrough the loading opening 37 so that it extends into the hopper 33,resting on the lower lip 58 and protruding outwardly therefrom, when thepacker blade 38 is moved from Position C downwardly to Position D, itsbottom edge 39 will strike such object. If the object cannot be brokenby the power applied thereto, the resulting sharp increase in pressurein the cylinders 44 which are extending during this movement along theleg C-D, results in transferring the hydraulic pressure to the cylinders41 which immediately extend their piston rods 49 to pick up" the packerblade 38 and move it forwardly above the refuse in the hopper 33. Thisreleases the item jammed between the lower edge 39 and the lip 58defining the bottom of the loading opening 37. The operator is signalledthat the cycle has not been properly completed and he may remove theobject which has caused the jam.

When a sufficient number of loads of refuse have been emptied into thehopper 33 and fed forwardly therefrom into the body 21, so that therefuse in the body 21 presents sufficient resistance to the forwardmovement of the packer blade 38 along the leg E-A, the packer blade 43cannot reach Position A. This results in the cylinders 41 not beingfully extended during this part of the cycle and the hydraulic pressurein their system reaches its maximum prior to the time the blade reachesits forward, body-closing Position A. This results in an indication tothe operator that the body 21 is filled and no further refuse can beaccumulated therein.

Having described our invention we claim:

1. A tailgate for loading refuse into the open rear end of a generallyrectangular refuse vehicle body,

said tailgate comprising, a rectangular frame mating with such open rearend of said vehicle body,

parallel vertical side walls extending rearwardly from said frame,

a hopper bottom extending across between said side walls,

the rear edges of said side walls and said bottom defining a loadingopening into said tailgate,

a generally rectangular packer blade extending across said tailgatebetween said side walls,

an inclined linear guide track comprising a linear slot in each of saidside walls extending upwardly toward said rectangular frame,

a cross member extending across the front upper end of said packer bladeand outwardly through said slots,

a rectangular slide block on each end of said cross member that isreciprocal in the respective one of said guide tracks,

each of said guide tracks also comprising an elongated three-sided guideoverlying the respective one of said slots in said side walls andconsisting of upper and lower parallel sides closely embracing upper andlower surfaces of said slide block and an outer side closely engagingthe outer side of said slide block, whereby said slide block isslidingly engaged with all three of said sides of said guide,

first extensible power cylinder means mounted on the outer sides of saidside walls and connected at their upper ends to the lower ends of saidslide blocks and at their lower ends to the rear lower portions of saidside walls in co-linear alignment with said guide tracks,

whereby the force applied by said first extensible power cylinder meansis directed along the colinear path defined by said guide tracks andsaid extensible power cylinders, and

a second pair of power cylinders pivotally mounted at one end adjacentthe upper rear corners of said side walls and pivotally connected tosaid packer blade at a point between the upper and lower ends thereof,

said first extensible power cylinder means and said second powercylinders being sequentially energized for cycling said packer bladethrough a packing cycle.

2. A tailgate according to claim 1 in which the hopper bottom has ashallow, generally V-shaped longitudinal section, the rear portionthereof extending forwardly and downwardly from the bottom edge of theopen rear end of said tailgate and the front portion thereof extendingupwardly and forwardly to the rear floor level of said refuse vehicle.

3. In a tailgate according to claim 1, the improvement comprisingdownwardly extending parallel guide bars mounted near the rear edges ofthe side walls and a roller mounted on each side of the shorter arm ofthe packer blade, said rollers engaging said guide bars near the end ofthe movement of the upper end of said packer blade downwardly along thepath for guiding the lower edge of said packer blade across the lowerreaches of the open rear end of said tailgate.

4. A tailgate according to claim 1 and pivot means connecting the upperforward corners of the side walls to the upper rear corners of therefuse vehicle body and power means for swinging said tailgate between alowered loading position and a raised discharge position. l l

1. A tailgate for loading refuse into the open rear end of a generallyrectangular refuse vehicle body, said tailgate comprising, a rectangularframe mating with such open rear end of said vehicle body, parallelvertical side walls extending rearwardly from said frame, a hopperbottom extending across between said side walls, the rear edges of saidside walls and said bottom defining a loading opening into saidtailgate, a generally rectangular packer blade extending across saidtailgate between said side walls, an inclined linear guide trackcomprising a linear slot in each of said side walls extending upwardlytoward said rectangular frame, a cross member extending across the frontupper end of said packer blade and outwardly through said slots, arectangular slide block on each end of said cross member that isreciprocal in the respective one of said guide tracks, each of saidguide tracks also comprising an elongated threesided guide overlying therespective one of said slots in said side walls and consisting of upperand lower parallel sides closely embracing upper and lower surfaces ofsaid slide block and an outer side closely engaging the outer side ofsaid slide block, whereby said slide block is slidingly engaged with allthree of said sides of said guide, first extensible power cylinder meansmounted on the outer sides of said side walls and connected at theirupper ends to the lower ends of said slide blocks and at their lowerends to the rear lower portions of said side walls in co-linearalignment with said guide tracks, whereby the force applied by saidfirst extensible power cylinder means is directed along the co-linearpath defined by said guide tracks and said extensible power cylinders,and a second pair of power cylinders pivotally mounted at one endadjacent the upper rear corners of said side walls and pivotallyconnected to said packer blade at a point between the upper and lowerends thereof, said first extensible power cylinder means and said secondpower cylinders being sequentially energized for cycling said packerblade through a packing cycle.
 2. A tailgate according to claim 1 inwhich the hopper bottom has a shallow, generally V-shaped longitudinalsection, the rear portion thereof extending forwardly and downwardlyfrom the bottom edge of the open rear end of said tailgate and the frontportion thereof extending upwardly and forwardly to the rear floor levelof said refuse vehicle.
 3. In a tailgate according to claim 1, theimprovement comprising downwardly extending parallel guide bars mountednear the rear edges of the side walls and a roller mounted on each sideof the shorter arm of the packer blade, said rollers engaging said guidebars near the end of the movement of the upper end of said packer bladedownwardly along the path for guiding the lower edge of said packerblade across the lower reaches of the open rear end of said tailgate. 4.A tailgate according to claim 1 and pivot means connecting the upperforward corners of the side walls to the upper rear corners of therefuse vehicle body and power means for swinging said tailgate between alowered loading position and a raised discharge position.